Object information acquiring apparatus and information processing apparatus

ABSTRACT

An object information acquiring apparatus, comprises a light irradiating unit configured to irradiate an object with light; a probe configured to receive an acoustic wave generated from the object and convert into an electrical signal; a characteristic information acquiring unit configured to acquire characteristic information relating to the object based on the electrical signal; an area information acquiring unit configured to acquire information relating to a reachable area of the light; a location detecting unit configured to acquire an operator location; and a determining unit configured to determine whether the operator location is in a first state where the operator location overlaps with the reachable area of the light or a second state where the operator location does not overlap with the reachable area of the light.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to an object information acquiringapparatus for acquiring information on an object.

Description of the Related Art

Object information acquiring apparatuses for acquiring information on anobject include photographing apparatuses using positron emissiontomography (PET), single-photon emission computed tomography (CT), andX-rays. Since such apparatuses use high-energy electromagnetic wavesincluding radioactive rays and present a risk of radiation exposure,measures must be taken involving, for example, having an operator (aphysician, a technician, or the like) relocate to another room duringphotography or having only an examinee enter the apparatus to undergophotography. Therefore, there are cases where immediate attention cannotbe given to an examinee experiencing anxiety or feeling unwell. Againstthis background, a medical apparatus is desired which enables anoperator to be present by an examinee's side during photography andwhich does not pose a burden on the operator.

Meanwhile, ultrasonic apparatuses are known as diagnostic apparatuseswhich are noninvasive to an object and, in particular, apparatuses usingphotoacoustic tomography (PAT) are attracting attention. PAT refers toan apparatus which, by irradiating an object with light such as laserlight, receives acoustic waves generated from the object and acquiresinformation on the object as image information. Since PAT uses lightinstead of radioactive rays to acquire object information, an operatorand an examinee can be present in a same space during photography (referto US Patent Application Publication No. 2013/0217995 (Specification)).

SUMMARY OF THE INVENTION

Since PAT uses high-output laser light, care must be taken to avoidirradiating parts other than a measurement object with the laser light.For example, an upper limit value of an intensity of light with which ahuman body can be irradiated is defined as maximum permissible exposure(MPE). Therefore, irradiation of parts other than a measurement objectpart on an object by light must be suppressed to the greatest extentfeasible.

However, with conventional apparatuses including the apparatus describedin US Patent Application Publication No. 2013/0217995 (Specification),there is a risk that a gap may be created between an object and theapparatus when the object moves during measurement and, consequently,laser light leaks into space.

The present invention has been made in consideration of such problemsexisting in prior art and an object thereof is to provide an objectinformation acquiring apparatus capable of suppressing irradiation oflaser light outside of an object.

The present invention in its one aspect provides an object informationacquiring apparatus, comprising a light irradiating unit configured toirradiate an object with light; an acoustic probe configured to receivean acoustic wave generated from the object due to the light and toconvert the acoustic wave into an electrical signal; a characteristicinformation acquiring unit configured to acquire characteristicinformation relating to the object based on the electrical signal; anarea information acquiring unit configured to acquire informationrelating to a reachable area of the light irradiated from the lightirradiating unit; a location detecting unit configured to acquire anoperator location which is a location of an operator; and a determiningunit configured to determine whether the operator location is in a firststate where the operator location overlaps with the reachable area ofthe light or a second state where the operator location does not overlapwith the reachable area of the light.

The present invention in its another aspect provides a control methodfor an object information acquiring apparatus including a lightirradiating unit which irradiates an object with light and an acousticprobe which receives an acoustic wave generated from the object due tothe light and which converts the acoustic wave into an electricalsignal, the control method comprising acquiring characteristicinformation relating to the object, based on the electrical signal;acquiring information relating to a reachable area of the lightirradiated from the light irradiating unit; acquiring an operatorlocation which is a location of an operator; and determining whether theoperator location is in a first state of where the operator locationoverlaps with the reachable area of the light or a second state wherethe operator location does not overlap with the reachable area of thelight.

The present invention in its another aspect provides an informationprocessing apparatus which determines whether or not to permitirradiation of an object with light by an object information acquiringapparatus, the information processing apparatus comprising an areainformation acquiring unit configured to acquire information relating toa reachable area of the light with which the object is irradiated; alocation detecting unit configured to acquire an operator location whichis a location of an operator of the object information acquiringapparatus; and a determining unit configured to determine whether theoperator location is in a first state where the operator locationoverlaps with the reachable area of the light or a second state wherethe operator location does not overlap with the reachable area of thelight.

According to the present invention, an object information acquiringapparatus capable of suppressing irradiation of laser light outside ofan object can be provided.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an external view of a photoacoustic apparatus according to afirst embodiment;

FIG. 2 is a system configuration diagram of the photoacoustic apparatusaccording to the first embodiment;

FIG. 3 is a sectional view of the photoacoustic apparatus according tothe first embodiment;

FIG. 4 is a diagram for explaining a modification of a locationdetecting unit;

FIG. 5 is a diagram for explaining a modification of a locationdetecting unit;

FIG. 6 is a diagram for explaining an example of a message displayed ona mobile terminal;

FIG. 7 is a flow chart of processes performed by the photoacousticapparatus according to the first embodiment; and

FIG. 8 is a flow chart of processes performed by the photoacousticapparatus according to the second embodiment.

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, embodiments of the present invention will be described indetail with reference to the drawings. It should be noted that samecomponents are generally assigned same reference numerals and adescription thereof will be omitted. In addition, it is to be understoodthat dimensions, materials, shapes, relative arrangements, and the likeof parts used in the description of the embodiments are intended to bechanged as deemed appropriate in accordance with configurations andvarious conditions of apparatuses to which the present invention is tobe applied and are not intended to limit the scope of the presentinvention.

First Embodiment

A photoacoustic apparatus according to the present embodiment is anapparatus which irradiates an object with pulse light and, by receivingand analyzing photoacoustic waves generated inside the object due to thepulse light, visualizes or, in other words, creates images ofcharacteristic information relating to optical characteristics insidethe object.

Characteristic information relating to optical characteristics generallyrefer to a distribution of generation sources or a distribution ofinitial sound pressure of acoustic waves, a distribution of opticalenergy absorption, a distribution of absorption coefficients, or adistribution of characteristics related to a concentration of asubstance constituting tissue in an object. Examples of a distributionof characteristics related to concentration include distributions ofoxygen saturation, a value obtained by weighting oxygen saturation withintensity of an absorption coefficient or the like, total hemoglobinconcentration, oxyhemoglobin concentration, and deoxyhemoglobinconcentration. In addition, a distribution of characteristics related toconcentration may be a distribution of glucose concentration, collagenconcentration, melanin concentration, or a volume fraction of fat orwater.

Moreover, an acoustic wave according to the present embodiment istypically an ultrasonic wave and includes an elastic wave which is alsoreferred to as a sonic wave, an ultrasonic wave, an acoustic wave, aphotoacoustic wave, or an optical ultrasonic wave. In addition, anacoustic wave generated by a photoacoustic effect is referred to as aphotoacoustic wave or an optical ultrasonic wave. Furthermore, in thepresent invention, light includes electromagnetic waves such as visiblelight and infrared light. Light with a specific wavelength can beappropriately selected according to a component set as a measurementobject of the apparatus.

<System Configuration>

A configuration of a photoacoustic apparatus according to the firstembodiment will be described.

FIG. 1 is an external view of the photoacoustic apparatus according tothe first embodiment, and FIG. 2 is a system configuration diagram ofthe photoacoustic apparatus according to the first embodiment.

A photoacoustic apparatus 10 according to the present embodimentincludes a light irradiating unit 11, an acoustic probe 12, a signalprocessing unit 13, an image display unit 14, a location detecting unit15, and a location determining unit 16.

In addition, a mobile terminal 20 is a terminal held by an operator 30of the apparatus and is equipped with a function for communicating withthe location determining unit 16 included in the photoacoustic apparatus10 and a function for presenting acquired information to the operator.

In the first embodiment, an object 40 is a human breast. Thephotoacoustic apparatus 10 according to the present embodiment is abed-type apparatus having an opening, in which measurements areperformed in a state where an examinee is lying down in a prone positionon a bed surface in an upper part of the apparatus and abreast isinserted into the opening provided in the upper part.

The light irradiating unit 11 and the acoustic probe 12 are arrangedinside the opening. FIG. 3 is an X-Z sectional view of the apparatus atthe opening. A supporting member 121 which is a hemispherical member isarranged in the opening of the apparatus, and the light irradiating unit11 and the acoustic probe 12 are arranged on an inner surface of thesupporting member 121. As shown in FIG. 2, the inserted breast isirradiated by laser light from the light irradiating unit 11 and theacoustic probe 12 receives acoustic waves created inside the breast.Subsequently, the signal processing unit 13 processes a signal output bythe acoustic probe and generates an image. The generated image is outputto and displayed by the image display unit 14.

Hereinafter, the respective units constituting the photoacousticapparatus according to the present embodiment will be described.

<<Light Irradiating Unit 11>>

The light irradiating unit 11 is a unit which is configured to irradiatean object with laser light (pulse light) and which is constituted by alight source and an optical member.

While the light source is desirably a laser light source in order toobtain a large output, a light-emitting diode, a flash lamp, or the likemay be used in place of a laser. When using a laser as the light source,various lasers such as a solid-state laser, a gas laser, a dye laser,and a semiconductor laser can be used. Timings, waveforms, intensity,and the like of irradiation are controlled by a light source controlunit (not shown). The light source control unit may be integrated withthe light source. While an alexandrite laser is used in the presentembodiment, a YAG laser, a titanium sapphire laser, and the like, may beused instead.

In addition, desirably, a wavelength of the pulse light is a specificwavelength which is absorbed by a specific component among componentsconstituting the object and which enables light to propagate to theinside of the object. Specifically, when the object is a livingorganism, light with a wavelength of 650 nm or more and 1100 nm or lessis desirably used. Moreover, when oxygen saturation is acquired asobject information, two or more wavelengths may be used.

Furthermore, in order to effectively generate a photoacoustic wave,light must be irradiated in a sufficiently short period of time inaccordance with thermal characteristics of the object. When the objectis a living organism, a pulse width of the generated pulse light ispreferably around 10 to 50 nanoseconds.

Moreover, while the example shown in FIG. 3 is configured such thatpulse light is directly irradiated from the light irradiating unit 11,only an emitting end may be arranged on a bottom surface of thesupporting member. In this case, the pulse light generated by the lightsource irradiates the object from the emitting end via an optical membersuch as a lens, a mirror, a diffuser plate, or an optical fiber.

Moreover, in the present embodiment, the pulse light is isotropicallyirradiated at an angle of 45 degrees as shown in FIG. 3. In addition,the supporting member 121 is configured so as to be independentlymovable by a scanning mechanism (not shown) from the bed surface holdingthe examinee and is capable of irradiating pulse light while changingpositions relative to the object. For example, a trajectory along whichthe supporting member 121 is moved can have a spiral shape. Moreover, adirection of movement may be a planar direction or a rotation direction.

In addition, while light irradiation is controlled by the light sourcecontrol unit (not shown) in the present embodiment, this configurationis not restrictive. For example, light irradiation may be controlled bya processor inside the mobile terminal 20.

<<Acoustic Probe 12>>

The acoustic probe 12 is a unit which is configured to detect anacoustic wave arriving from inside an object and to convert the acousticwave into an analog electrical signal. The probe is also referred to asan acoustic probe, an acoustic detector, or a transducer. As the probe,any kind of probe may be used including those using a piezoelectricphenomenon, optical resonance, or a variation in capacitance.

Since acoustic waves generated by a living organism are ultrasonic wavesfrom 100 kHz to 100 MHz, an element capable of receiving this frequencyband is used as the acoustic probe 12. Specifically, a transducer usinga piezoelectric phenomenon, a transducer using optical resonance, atransducer using a variation in capacity, or the like can be used.

In addition, desirably, an acoustic probe having a high receivingsensitivity and a wide frequency band is used. Specific examples of theacoustic probe include a piezoelectric element using leadzirconatetitanate (PZT) or the like, a capacitive micromachinedultrasonic transducer (CMUT), and a probe using a Fabry-Perotinterferometer. However, the acoustic probe is not limited to theseexamples and any probe may be used as long as functions as a probe aresatisfied.

Furthermore, the acoustic probe may be an arrangement of a plurality ofacoustic elements. Simultaneously receiving acoustic waves at aplurality of positions enables measurement time to be shortened and aneffect of vibration of the object and the like to be reduced.

In the present embodiment, an acoustic probe is formed by providing theillustrated hemispherical supporting member 121 and arranging aplurality of acoustic elements on an inner surface of the supportingmember 121.

<<Signal Processing Unit 13>>

The signal processing unit 13 is a unit which is configured to amplifythe analog electrical signal output by the acoustic probe 12 and toconvert the analog electrical signal into a digital signal. The signalprocessing unit 13 is typically constituted by an amplifier, an A/Dconverter, a field programmable gate array (FPGA) chip, or the like.When a plurality of signals are obtained from the acoustic probe 12,desirably, a plurality of signals can be processed simultaneously.

In addition, the signal processing unit 13 is also a unit configured toprocess a digitally-converted signal (hereinafter, a photoacousticsignal) and to reconstruct an image representing characteristicinformation inside the object (a characteristic information acquiringunit according to the present invention). While methods ofreconstruction include a Fourier transform method, a universalback-projection method (UBP method), and a filtered back-projectionmethod, any method may be used.

In addition, a configuration may be adopted in which functionalinformation (such as oxygen saturation) inside the object is calculatedby processing a photoacoustic signal obtained through irradiation ofirradiation light with a plurality of wavelengths.

<<Image Display Unit 14>>

The image display unit 14 is a unit which is configured to display theimage output from the signal processing unit 13. For example, a liquidcrystal display, a plasma display, an organic EL display, an FED, or thelike can be used as a display apparatus. Moreover, the display apparatusmay be provided separate from the photoacoustic apparatus. For example,acquired object information may be transmitted to an external displayapparatus in a wired or wireless manner.

<<Location Detecting Unit 15 and Mobile Terminal 20>>

The location detecting unit 15 is a unit which is configured to acquirea location of an operator (hereinafter, an operator location) relativeto the apparatus. In addition, the mobile terminal 20 is a smallcomputer held by the operator (for example, a physician or a technician)of the photoacoustic apparatus 10.

In the present embodiment, the location detecting unit 15 is a locationreceiver which detects a location of a target (the mobile terminal 20)using an RFID system and which outputs coordinates of the location.

The location receiver constituting the location detecting unit 15 isarranged at four corners of a room in which the photoacoustic apparatus10 is installed. The mobile terminal 20 includes an RFID tag and areceiver having received a transmitted signal detects a location of themobile terminal 20. Moreover, while the location of the mobile terminal20 is expressed by a coordinate system with the room in which thephotoacoustic apparatus 10 is installed as a reference in the presentembodiment, this configuration is not necessarily restrictive.

Moreover, the location detecting unit 15 may use a camera such as thatshown in FIG. 4 and detect an operator location based on an acquiredcamera image (in this case, the mobile terminal 20 is not necessaryrequired). In addition, an antenna (or a sensor) arranged at a locationsuch as that shown in FIG. 5 can be used as the location detecting unit15.

Alternatively, an operator location may be detected using a beacon or aninfrared sensor. A LAN card or an LED marker can also be used instead ofthe RFID tag. Alternatively, a location of the mobile terminal may bedetected using GPS, a Wi-Fi™ network, or a Bluetooth™ network. Whenusing GPS, a location of the mobile terminal is determined based onlatitude and longitude information. In this case, the operator locationcan be identified by registering, in advance, latitude and longitudeinformation on the room in which the photoacoustic apparatus 10 isinstalled. Moreover, in the present embodiment, an error of the operatorlocation obtained by the location detecting unit is favorably kept toseveral 10 cm or less and more favorably kept to several cm and less. Inthis case, a beacon or a location receiver is favorably adopted as thelocation detecting unit.

Moreover, when a beacon is used, the mobile terminal 20 may receive aradio wave transmitted from the beacon and the mobile terminal 20 maycalculate and transmit its own location. A combination of the locationdetecting unit 15 and a method of detecting a location can be selectedas appropriate.

In addition, while an operator location is expressed by coordinates ofthe mobile terminal in the present embodiment, the operator location maybe expressed using coordinates other than those of the terminal. Forexample, coordinates of a representative point of the body (a locationof a center of gravity point or the eyes) of the operator may be used.

Furthermore, the operator location need not necessarily be expressed bya point. For example, when an area (or an approximate area) where thebody of the operator is present can be acquired two-dimensionally orthree-dimensionally by means such as a camera or a sensor, the operatorlocation can be expressed by information of the area (or the approximatearea).

In addition to the functions described above, the mobile terminal 20 hasa function of receiving and notifying the operator of a determinationresult generated by the location determining unit 16 to be describedlater. While the mobile terminal 20 is typically a portable computersuch as a tablet PC, a mobile phone, a watch or other devices may beused instead. In addition, the mobile terminal 20 may partially assumethe role of the photoacoustic apparatus 10 and perform the control andthe location determining function thereof.

<<Location Determining Unit 16>>

The location determining unit 16 is a unit which is configured tocompare the operator location acquired by the location detecting unit 15with area information set in advance and to transmit a comparison resultto the mobile terminal 20.

In the present embodiment, the location determining unit 16 storesinformation on an area (hereinafter, a light reachable area) which isreachable by primary light of the pulse light irradiated from the lightirradiating unit 11 (an area information acquiring unit according to thepresent invention). In addition, the location determining unit 16determines whether or not location information of the mobile terminal 20as acquired by the location detecting unit 15 is within the lightreachable area (a determining unit according to the present invention).A determination result is transmitted to the mobile terminal 20.

In the present embodiment, a maximum reachable range of the primarylight on a ceiling of the room and a columnar three-dimensional areaobtained by drawing down the range in a vertical direction to a floorare defined as the light reachable area. For example, let us consider acase where pulse light is emitted in a spiral direction at a maximumangle of 45 degrees around an emitting end of the light irradiatingunit. In this case, for example, when a height from the emitting end tothe ceiling of the room is 1.5 meters, primary light reaches a rangewith a radius of 1.5 meters around the emitting end on the ceiling. Inother words, the light reachable area is a columnar area obtained byprojecting the range toward the floor in the vertical direction.

Moreover, while the location determining unit 16 is assumed to be anindependent personal computer in the present embodiment, when thephotoacoustic apparatus 10 is controlled by a computer, hardware may beused in combination. Alternatively, an apparatus other than a personalcomputer may be used. In addition, the location detecting unit 15 may beequipped with the functions of the location determining unit 16.

The location determining unit 16 determines whether or not the operatorlocation (in other words, coordinates of the mobile terminal 20) and thelight reachable area overlap each other or, in other words, whether ornot the operator location is included in the light reachable area, andtransmits a determination result to the mobile terminal 20.

In this case, when the operator location and the light reachable areaoverlap each other, the location determining unit 16 determines that atleast a part of the operator's body is within the light reachable area.

Moreover, when determining overlapping, coordinates may be simplycompared with each other or a location or an area where the operator ispresent may be assumed based on acquired coordinates and the assumedarea may be compared with the light reachable area. For example, theoperator may be assumed to be present in a range with a radius of 50 cmaround a location of the mobile terminal 20 as acquired by the locationdetecting unit 15, and a determination may be made on whether or not therange overlaps with the light reachable area set in advance. In otherwords, an area with a radius of 50 cm around the location of the mobileterminal 20 may be considered the operator location. Accordingly, areliable determination can be made even when accuracy of locationdetection is not high.

Alternatively, when the operator location is expressed bytwo-dimensional or three-dimensional information, a determination may bemade on whether or not at least a part of the operator's body is insidethe light reachable area. In addition, since a part of the operator'sbody with lowest MPE is the retina, a location of the eyes may beestimated using a known method and a determination may be made onwhether or not the estimated location of the eyes is within the lightreachable area.

<Notification Method of Determination Result>

Next, a method of issuing notification on a result of a determinationperformed by the location determining unit 16 will be described.

In the present embodiment, a communicating unit provided in the locationdetermining unit 16 transmits a determination result to the mobileterminal 20, and the mobile terminal 20 causes the determination resultto be displayed on a display of the mobile terminal 20. Moreover, whenthe mobile terminal 20 is not used, the determination result may bedisplayed on a PC display, a television, or a monitor. More favorably,the notification is only made to the operator so as not to give theexaminee cause for anxiety. In the present embodiment, only the operatoris notified of the determination result by displaying a message on amonitor of the mobile terminal 20 held by the operator. In this case, adisplay as a display unit also functions as a notifying unit.

An example of a message displayed on the mobile terminal 20 is shown inFIG. 6. Favorably, for example, the message simply indicates whether ameasurement can be performed or not. Alternatively, a status such as“measurement in progress” or “irradiation in progress” may be displayed.The fact that measurement cannot be started or a suggestion that theoperator should move away from the apparatus may be displayed instead.Alternatively, for example, a direction of the light reachable area, adistance until entering the light reachable area, or a direction ofmovement or a movement distance in order to exit the light reachablearea may be displayed.

Instead of displaying a message, a determination result may be notifiedby causing the mobile terminal 20 to vibrate. In this case, the mobileterminal 20 itself may be vibrated or another device worn or carried bythe operator may be vibrated. Alternatively, the operator may benotified with both message display and vibration. Sound may also be usedin combination. Besides the above, any means of notification may beadopted as long as the operator can be notified of a determinationresult.

Moreover, when the mobile terminal 20 has a function for controllinglight irradiation, a button or an icon for starting laser irradiationmay be displayed on the mobile terminal and irradiation may be startedin accordance with an operation of the button or the icon. In this case,a specification may be adopted in which, when it is determined that theoperator location is within the light reachable area, the button or theicon is grayed out to prevent irradiation from being started.

Alternatively, a determination result may be displayed on a monitorinstalled near the feet of the examinee. By adopting such aconfiguration, only the operator can be notified of the determinationresult.

<Process Flow>

Next, a process flow chart of the photoacoustic apparatus according tothe present embodiment is shown in FIG. 7.

While a mode in which the mobile terminal 20 has a function ofcontrolling light irradiation will be described below, the process flowchart may also be applied to other modes.

When the operator presses an irradiation start button displayed on ascreen of the mobile terminal 20, the processes are started (step S11).

Next, a location receiver that is the location detecting unit 15 checksa location of the mobile terminal 20 to which an RFID tag is attached(step S12). When the tag is recognized, the location detecting unit 15determines coordinates of the mobile terminal based on a location of thetag and transmits the coordinates to the location determining unit 16(step S13).

Next, the location determining unit 16 compares a light reachable areastored in advance and the coordinates of the mobile terminal transmittedfrom the location detecting unit with each other and determines whetheror not the light reachable area and the coordinates overlap each other(step S14). A determination result is transmitted to and displayed bythe mobile terminal (steps S15 and S16).

At this point, when the operator location is outside of the lightreachable area, irradiation of laser light is permitted and irradiationis started (step S17). On the other hand, when the operator location iswithin the light reachable area, irradiation of laser light is notperformed (step S18) and the process returns to step S11. In this case,the operator relocates and once again performs an operation for startingirradiation. In other words, the light irradiating unit 11 does notpermit irradiation of light when the operator location is included in areachable area of the light.

According to the first embodiment, a measurement of an object can bestarted only when an operator of the apparatus is outside of an areawhich may be reached by primary light of laser light. In other words,irradiation of the laser light outside of an examinee can be prevented.In addition, since the examinee is not notified of a determinationresult, an effect of not giving the examinee unnecessary cause foranxiety is produced.

Moreover, while the processes shown in FIG. 7 are executed when theoperator performs an operation for starting a measurement in the firstembodiment, determinations may be repetitively performed during ameasurement and irradiation of pulse light may be stopped immediatelywhen it is determined that the operator is within the light reachablearea.

Second Embodiment

In the first embodiment, when the operator is within a light reachablearea, the fact that the operator is within the light reachable area isnotified and control is performed so as not to irradiate laser light. Incontrast, in the second embodiment, irradiation of laser light isconditionally permitted in consideration of maintenance of theapparatus.

A configuration of a photoacoustic apparatus according to the secondembodiment is similar to that of the first embodiment with the exceptionof the process described below.

In maintenance of the photoacoustic apparatus, operations of the lightirradiating unit and the acoustic probe must be checked in a state wherean object is absent. In addition, during the operation check, there maybe cases where pulse light must be irradiated even when an operator (amaintenance person) of the apparatus is within the light reachable area.

In consideration thereof, in the second embodiment, control is performedso as to enable irradiation of pulse light on condition that use ofprotective gear is confirmed even when an operator location is withinthe light reachable area.

The photoacoustic apparatus according to the second embodiment isconfigured so as to be switchable to a maintenance mode (a second modeaccording to the present invention) which differs from an ordinary mode(a first mode according to the present invention: hereinafter, a usermode). FIG. 8 shows a process flow chart in the maintenance mode.

In the maintenance mode, when it is determined that the operatorlocation is within the light reachable area, step S21 for determiningwhether or not protective gear (in the present example, safety glasses)is worn is executed.

Processes performed in the user mode is as shown in FIG. 7. In otherwords, step S21 is not executed in the user mode.

In the second embodiment, when issuing notification on a determinationresult in step S16, a message prompting use of safety glasses isdisplayed. In addition, in step S21, a message for confirming whethersafety glasses are worn is displayed and a user is asked to selecteither Yes or No using an input unit. As the input unit, a mouse, akeyboard, a touch panel mounted to the mobile terminal 20, or the likecan be adopted.

At this point, irradiation of light is started when Yes is selectedwhile the process of step S11 and thereafter is performed once againwhen No is selected. In other words, irradiation of light is notpermitted when safety glasses are not worn.

As described above, in the second embodiment, since irradiation of pulselight irradiation is conditionally permitted even when an operator ofthe apparatus is within an area which may be reached by primary light,convenience when performing maintenance is improved.

Moreover, switching between the user mode as the first mode and themaintenance mode as the second mode may be performed based on aninstruction from the mobile terminal 20 or may be performed by anapparatus main body. In addition, the photoacoustic apparatus may beautomatically switched to the maintenance mode when a part of theapparatus is removed.

In the present example, the operator is asked to select whether safetyglasses are worn or not. Alternatively, in step S21, whether or notsafety glasses are worn may be automatically detected and control may beperformed based on a detection result. For example, when the locationdetecting unit 15 includes a camera, a face of a person and whether ornot safety glasses are worn may be detected by analyzing an image.Alternatively, the camera may be provided in a unit independent of thelocation detecting unit 15. For example, the camera may be built intothe mobile terminal 20. In this case, the operator may be asked to havehis or her own face recognized using the built-in camera. In this case,the camera which photographs the operator's face and a processor whichanalyzes a camera image function as a detecting unit which detectswhether or not the operator wears safety glasses. Moreover, at thispoint, a camera image used to determine an operator location may also beused to determine whether or not safety glasses are worn.

Alternatively, the safety glasses may include a contact sensorconstituted by a pressure sensor or the like, and a determination thatthe safety glasses are worn may be made when the contact sensor detectsthat the operator and the safety glasses have come into contact witheach other. In this case, the contact sensor functions as a detectingunit which detects whether or not the operator wears safety glasses.

(Modification)

It is to be understood that the descriptions of the respectiveembodiments merely represent examples of the present invention and, assuch, the present invention can be implemented by appropriatelymodifying or combining the embodiments without departing from the spiritand the scope of the invention.

For example, the present invention may be implemented as an objectinformation acquiring apparatus which includes at least a part of theprocesses described above. The present invention may also be implementedas an object information acquiring method which includes at least a partof the processes described above. The present invention may also beimplemented as an information processing apparatus which determineswhether or not laser light is being irradiated in combination with anobject information acquiring apparatus. The present invention may alsobe implemented as an information processing method performed by theinformation processing apparatus. The processes and units describedabove may be implemented in any combination insofar as technicalcontradictions do not occur.

Other Embodiments

Embodiment(s) of the present invention can also be realized by acomputer of a system or apparatus that reads out and executes computerexecutable instructions (e.g., one or more programs) recorded on astorage medium (which may also be referred to more fully as a‘non-transitory computer-readable storage medium’) to perform thefunctions of one or more of the above-described embodiment(s) and/orthat includes one or more circuits (e.g., application specificintegrated circuit (ASIC)) for performing the functions of one or moreof the above-described embodiment(s), and by a method performed by thecomputer of the system or apparatus by, for example, reading out andexecuting the computer executable instructions from the storage mediumto perform the functions of one or more of the above-describedembodiment(s) and/or controlling the one or more circuits to perform thefunctions of one or more of the above-described embodiment(s). Thecomputer may comprise one or more processors (e.g., central processingunit (CPU), micro processing unit (MPU)) and may include a network ofseparate computers or separate processors to read out and execute thecomputer executable instructions. The computer executable instructionsmay be provided to the computer, for example, from a network or thestorage medium. The storage medium may include, for example, one or moreof a hard disk, a random-access memory (RAM), a read only memory (ROM),a storage of distributed computing systems, an optical disk (such as acompact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™),a flash memory device, a memory card, and the like.

While the present invention has been described with reference toexemplary embodiments, it is to be understood that the invention is notlimited to the disclosed exemplary embodiments. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all such modifications and equivalent structures andfunctions.

This application claims the benefit of Japanese Patent Application No.2016-033354, filed on Feb. 24, 2016, which is hereby incorporated byreference herein in its entirety.

What is claimed is:
 1. An object information acquiring apparatus,comprising: a light irradiating unit configured to irradiate an objectwith light; an acoustic probe configured to receive an acoustic wavegenerated from the object due to the light and to convert the acousticwave into an electrical signal; a characteristic information acquiringunit configured to acquire characteristic information relating to theobject based on the electrical signal; an area information acquiringunit configured to acquire information relating to a reachable area ofthe light irradiated from the light irradiating unit; a locationdetecting unit configured to acquire an operator location which is alocation of an operator; and a determining unit configured to determinewhether the operator location is in a first state where the operatorlocation overlaps with the reachable area of the light or a second statewhere the operator location does not overlap with the reachable area ofthe light.
 2. The object information acquiring apparatus according toclaim 1, wherein the light irradiating unit is configured not to permitirradiation of light when the operator location is in the first state,based on a determination result of the determining unit.
 3. The objectinformation acquiring apparatus according to claim 1, wherein the lightirradiating unit is configured to perform switching between a first modein which irradiation of light is not permitted when the operatorlocation is in the first state, based on a determination result of thedetermining unit and a second mode in which irradiation of light ispermitted even when the operator location is in the first state, basedon a determination result of the determining unit.
 4. The objectinformation acquiring apparatus according to claim 3, further comprisingan input unit configured to accept an input regarding whether or not theoperator wears safety glasses, wherein the light irradiating unit isconfigured to permit irradiation of light in the second mode oncondition that information indicating that the safety glasses are wornis acquired from the input unit.
 5. The object information acquiringapparatus according to claim 4, wherein the input unit is configured toprevent an input regarding whether or not the operator wears safetyglasses when the light irradiating unit is in the first mode.
 6. Theobject information acquiring apparatus according to claim 3, furthercomprising a detecting unit configured to detect whether or not theoperator wears safety glasses, wherein the light irradiating unit isconfigured to permit irradiation of light in the second mode oncondition that the detecting unit detects that the safety glasses areworn.
 7. The object information acquiring apparatus according to claim6, wherein the light irradiating unit is configured to permitirradiation of light in the first mode, based on a determination resultof the determining unit regardless of a detection result of thedetecting unit.
 8. The object information acquiring apparatus accordingto claim 6, wherein the location detecting unit is configured to acquirethe operator location from a camera image, and the detecting unit isconfigured to detect whether or not the operator wears safety glasses,based on the camera image.
 9. The object information acquiring apparatusaccording to claim 1, further comprising a notifying unit configured toperform a notification for prompting the use of safety glasses.
 10. Theobject information acquiring apparatus according to claim 1, furthercomprising a notifying unit configured to issue notification on adetermination result of the determining unit.
 11. The object informationacquiring apparatus according to claim 1, wherein the operator locationis a location corresponding to at least a part of the operator's body.12. The object information acquiring apparatus according to claim 1,wherein the location detecting unit is configured to estimate a locationof the eyes of the operator and consider the estimated location of theeyes as the operator location.
 13. The object information acquiringapparatus according to claim 1, wherein the location detecting unit isconfigured to acquire the operator location, based on informationreceived from a terminal carried by the operator.
 14. The objectinformation acquiring apparatus according to claim 1, wherein thelocation detecting unit is configured to include one or more beacons andto acquire the operator location by receiving, from a terminal carriedby the operator, location information generated based on a signaltransmitted from the beacon.
 15. A control method for an objectinformation acquiring apparatus including a light irradiating unit whichirradiates an object with light and an acoustic probe which receives anacoustic wave generated from the object due to the light and whichconverts the acoustic wave into an electrical signal, the control methodcomprising: acquiring characteristic information relating to the object,based on the electrical signal; acquiring information relating to areachable area of the light irradiated from the light irradiating unit;acquiring an operator location which is a location of an operator; anddetermining whether the operator location is in a first state of wherethe operator location overlaps with the reachable area of the light or asecond state where the operator location does not overlap with thereachable area of the light.
 16. An information processing apparatuswhich determines whether or not to permit irradiation of an object withlight by an object information acquiring apparatus, the informationprocessing apparatus comprising: an area information acquiring unitconfigured to acquire information relating to a reachable area of thelight with which the object is irradiated; a location detecting unitconfigured to acquire an operator location which is a location of anoperator of the object information acquiring apparatus; and adetermining unit configured to determine whether the operator locationis in a first state where the operator location overlaps with thereachable area of the light or a second state where the operatorlocation does not overlap with the reachable area of the light.